package com.raptor.common.util;

import java.io.File;
import java.io.FileFilter;
import java.io.IOException;
import java.net.JarURLConnection;
import java.net.URL;
import java.net.URLDecoder;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.List;
import java.util.jar.JarEntry;
import java.util.jar.JarFile;

public class ClassUtil {


    public static List<Class<?>> getClasses(String[] packageNames) {


        List<Class<?>> classes = new ArrayList<Class<?>>();

        for (int i = 0; i < packageNames.length; i++) {


            boolean recursive = true;
            String packageName = packageNames[i];

            String packageDirName = packageName.replace('.', '/');

            Enumeration<URL> dirs;
            try {
                dirs = Thread.currentThread().getContextClassLoader().getResources(packageDirName);

                while (dirs.hasMoreElements()) {

                    URL url = dirs.nextElement();

                    String protocol = url.getProtocol();

                    if ("file".equals(protocol)) {
                        String filePath = URLDecoder.decode(url.getFile(), "UTF-8");
                        findAndAddClassesInPackageByFile(packageName, filePath, recursive, classes);
                    } else if ("jar".equals(protocol)) {

                        JarFile jar;
                        try {

                            jar = ((JarURLConnection) url.openConnection()).getJarFile();

                            Enumeration<JarEntry> entries = jar.entries();

                            while (entries.hasMoreElements()) {

                                JarEntry entry = entries.nextElement();
                                String name = entry.getName();

                                if (name.charAt(0) == '/') {

                                    name = name.substring(1);
                                }

                                if (name.startsWith(packageDirName)) {
                                    int idx = name.lastIndexOf('/');

                                    if (idx != -1) {

                                        packageName = name.substring(0, idx).replace('/', '.');
                                    }

                                    if ((idx != -1) || recursive) {

                                        if (name.endsWith(".class") && !entry.isDirectory()) {

                                            String className = name.substring(packageName.length() + 1, name.length() - 6);
                                            try {

                                                classes.add(Class.forName(packageName + '.' + className));
                                            } catch (ClassNotFoundException e) {
                                                e.printStackTrace();
                                            }
                                        }
                                    }
                                }
                            }
                        } catch (IOException e) {
                            e.printStackTrace();
                        }
                    }
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return classes;
    }


    private static void findAndAddClassesInPackageByFile(String packageName, String packagePath, final boolean recursive, List<Class<?>> classes) {

        File dir = new File(packagePath);

        if (!dir.exists() || !dir.isDirectory()) {
            return;
        }

        File[] dirfiles = dir.listFiles(new FileFilter() {

            public boolean accept(File file) {
                return (recursive && file.isDirectory()) || (file.getName().endsWith(".class"));
            }
        });

        for (File file : dirfiles) {

            if (file.isDirectory()) {
                findAndAddClassesInPackageByFile(packageName + "." + file.getName(), file.getAbsolutePath(), recursive, classes);
            } else {

                String className = file.getName().substring(0, file.getName().length() - 6);
                try {

                    classes.add(Class.forName(packageName + '.' + className));
                } catch (ClassNotFoundException e) {
                    e.printStackTrace();
                }
            }
        }
    }
}
